Emerging systems that benefit from an energy storage capacity with high voltage and high power capabilities often utilize capacitor-type devices such as conventional electrochemical capacitors or capacitors having a hybrid form based on electrolytic devices. Capacitors can be widely used for applications ranging from electrical circuitry and power delivery to voltage regulation and battery replacement. The total energy that a capacitive device can store can be determined by the useful surface area of the device, the distance of the spacing and its permittivity between the accumulated charges, and the square of the voltage of the space.
As capacitor technology has continued to develop, several types have emerged. As one example, electric double-layer capacitors (EDLCs), also referred to as ultracapacitors, are characterized by high energy storage and power density, small size, and low weight and have thus become promising candidates for use in several applications. Conventional EDLCs, however, tend to have substantially limited applicable voltage of just a few volts. On the other hand, conventional electrolytic capacitors operate at high voltage (up to hundreds volts) but with limited surface areas resulting in lower energy capacity.